A color liquid crystal display comprises color filters corresponding to a color to be displayed per pixel. As a method for manufacturing a color filter, conventionally, a pigment dispersion method of repeating a photolithography process for a plurality of times, or the like has been used. Recently, for the main purpose of cost reduction, a method of using an ink jet apparatus attracts the attention.
The pattern pitch of a color filter tends to be finer and finer according to the high definition of the color liquid crystal displays. The amount of ink discharged from the ink jet apparatus is a few pico liter, and thus it is extremely small. In order to form a pattern of a small line width, it is necessary to have a small discharging amount. Also in this regard, the ink jet apparatus is preferable for the manufacturing a color filter.
According to the ink jet apparatus, a color filter pattern is produced, in general, by using a head unit provided with a plurality of piezoelectric driving type heads.
However, due to mechanical and electric variation of each piezoelectric driving type heads, the liquid droplet amount discharged form each piezoelectric driving type head is uneven although the same driving pulse is applied. If the ink discharging amount is not even, the thickness of the coloring layer or the like constituting the color filter becomes uneven.
That is, when a color filter is manufactured by using the conventional ink jet apparatus, derived form the uneven ink discharging amount, there is a problem that unevenness of the display color of the color filter is generated.